Hi Russo, you can, actually almost must, add fresh coal to the mound of red coal. Otherwise you must build a fire from new with wood again.
You need to shake the ashes from the existing coal fire, to open up the air passageways around the pieces of coal. The powdery ash tends to block the air flow through the grates and up through the coal bed.
Load on the coal, you want a full firebox, all the way up to the top of the firebrick lining the firebox. Then control the heat output and lenght of burn with the air getting to the fire.
With 10" of coal you should burn all night long, as long as you don't have too much air to the fire.
All air to the coal must come from under the fire, up through the grate. No air entering the firebox from above the fire. Don't leave any edges of the coal bed open to let air get by the coal bed, all air must go through the coal.
Hope this helps, Greg L..
Last edited by LsFarm
on Mon Mar 05, 2007 1:27 am, edited 1 time in total.